Implement streaming protocol (mw_feed_...)

diff --git a/metawatch.c b/metawatch.c
index 5c5b73bfea3c36f3d939cf84d82d251964d56d6d..4576d9f6d175a16df63ce79f7180b76cfe3b5287 100644 (file)
--- a/metawatch.c
+++ b/metawatch.c
@@ -480,7 +480,7 @@ void mw_set_status_change_event_cb(mwdevice_t *mwdevice, void (*mw_status_change
  * Protocol handling
  * ---------------------------------------------------------------------- */
 
-int decode_frame(mwdevice_t *mwdevice, unsigned char *buf, int len)
+int mw_decode_frame(mwdevice_t *mwdevice, unsigned char *buf, int len)
 {
        unsigned short crc;
        unsigned char msglen;
@@ -547,6 +547,38 @@ int decode_frame(mwdevice_t *mwdevice, unsigned char *buf, int len)
 }
 
 
+int mw_feed_msg_buffer(mwdevice_t *mwdevice, unsigned char *buf, int len)
+{
+       char msgbuf[64];
+       int tlen;
+
+       if (len <= 0)
+               return -1;
+
+       memcpy((mwdevice->pbuf+mwdevice->pbuf_len), buf, len);
+       mwdevice->pbuf_len += len;
+       
+       while (mwdevice->pbuf_len > 0) {
+               /* scan for MW_SOF */
+               while (mwdevice->pbuf[0] != MW_SOF) {
+                       memmove(mwdevice->pbuf, (mwdevice->pbuf+1), --mwdevice->pbuf_len);
+               }
+               tlen = mwdevice->pbuf[1];
+               /* OK, there is an SOF but the message is too short */
+               if (tlen > mwdevice->pbuf_len) {
+                       /* we have to wait for more data to come in */
+                       break;
+               }
+               /* here we have a complete msg */
+               memcpy(msgbuf, mwdevice->pbuf, tlen);
+               mw_decode_frame(mwdevice, msgbuf, tlen);
+               memmove(mwdevice->pbuf, (mwdevice->pbuf+tlen), tlen);
+               mwdevice->pbuf_len -= tlen;
+       }
+       return 0;
+}
+
+
 /* ----------------------------------------------------------------------
  * General code usage
  * ---------------------------------------------------------------------- */
@@ -555,6 +587,8 @@ int mw_init(mwdevice_t *mwdevice, int mw_fd)
 {
        memset(mwdevice, 0, sizeof(mwdevice_t));
        mwdevice->mw_fd = mw_fd;
+       memset(mwdevice->pbuf, 0, MW_PBUF_LEN);
+       mwdevice->pbuf_len = 0;
 
        /* figure out which device we run with */
        mw_send_frame(mwdevice, MW_GET_DEVICE_TYPE, 0, NULL, 0);

diff --git a/metawatch.h b/metawatch.h
index 5df07a07493d70242c29e29467eece3e5e52204e..4fbbc9bbe25b7e3de13f447870aff0e4b8391a20 100644 (file)
--- a/metawatch.h
+++ b/metawatch.h
@@ -10,8 +10,12 @@
 #include <time.h>
 #include "metawatch_protocol.h"
 
+#define MW_PBUF_LEN 512
+
 typedef struct _mwdevice_t {
        int mw_fd;              /* file decriptor for MW connection */
+       char pbuf[MW_PBUF_LEN]; /* protocol receive buffer */
+       int pbuf_len;
        unsigned char devtype;  /* the device type of the connected device */
        /* watch message callbacks */
        void (*mw_get_device_type_response_cb) (struct _mwdevice_t *mwdevice, unsigned char devtype, void *user_data);
@@ -79,7 +83,9 @@ int mw_disable_button(mwdevice_t *mwdevice, unsigned char mode, unsigned char bu
 
 int mw_advance_watch_hands(mwdevice_t *mwdevice, unsigned char hours, unsigned char minutes, unsigned char seconds);
 
-int decode_frame(mwdevice_t *mwdevice, unsigned char *buf, int len);
+int mw_decode_frame(mwdevice_t *mwdevice, unsigned char *buf, int len);
+
+int mw_feed_msg_buffer(mwdevice_t *mwdevice, unsigned char *buf, int len);
 
 int mw_init(mwdevice_t *mwdevice, int mw_fd);
 

diff --git a/mw_main.c b/mw_main.c
index dd4e4a418854697272b400113a153aa2888350c8..a5c108327cd3743b97a426305b575b2cea548184 100644 (file)
--- a/mw_main.c
+++ b/mw_main.c
@@ -448,7 +448,7 @@ gboolean handle_mw_io(GIOChannel *mw_io, GIOCondition condition, gpointer udata)
        mwdata_t *mdata = (mwdata_t *)udata;
        int rcvd;
 
-       rcvd = read(mdata->mwdevice.mw_fd, mdata->rcvbuf+mdata->rcvbuf_pos, 64);
+       rcvd = read(mdata->mwdevice.mw_fd, mdata->rcvbuf, 64);
 #ifdef DEBUG
        fprintf(stderr, "read %d bytes:\n", rcvd);
 #endif
@@ -456,8 +456,7 @@ gboolean handle_mw_io(GIOChannel *mw_io, GIOCondition condition, gpointer udata)
 #ifdef DEBUG
                dump_frame(mdata->rcvbuf, rcvd);
 #endif
-               decode_frame(&mdata->mwdevice, mdata->rcvbuf, rcvd);
-               mdata->rcvbuf_pos = 0;
+               mw_feed_msg_buffer(&mdata->mwdevice, mdata->rcvbuf, rcvd);
        }
 
        return TRUE;